Hypertension (HT) during adolescence tracks into adulthood, contributing to adult cardiovascular morbidity and mortality. National guidelines for the diagnosis and treatment of hypertension in children and adolescents were developed by the National High Blood Pressure Education Program (NHBPEP); their Fourth Report was published in 2004. Despite heightened awareness of hypertension in pediatric populations, most adolescents with elevated blood pressure remain clinically unrecognized. Factors that contribute to this gap in care include: the need to translate adolescent blood pressure (BP) measures into BP percentiles on the basis of age, gender, and height, lack of familiarity with NHBPEP clinical guidelines, and competing demands at clinical encounters. Electronic health record (EHR)-based clinical decision support (CDS) can be used to address these barriers and support better care of elevated BP and HT in adolescents. In this project, we integrate EHR-extracted data with sophisticated Web-based CDS algorithms to provide patient-specific point-of-care clinical recommendations, in accordance with NHBPEP guidelines. To evaluate the impact of this innovation on quality and cost of care, we randomize 18 clinics with their 130 pediatric care providers (PCP) and their estimated 17,000 adolescent patients to receive or not receive this EHR-based CDS intervention. We hypothesize that the intervention will improve recognition and early management of elevated BP and that short-term increases in outpatient care costs will be offset by longer-term clinical benefits, estimated using established econometric models. This innovative project (a) addresses the under-recognized high-risk patient population of adolescents, (b) integrates EHR and Web-based CDS technology to provide sophisticated patient-specific point-of-care CDS, (c) develops and implements novel and intuitive visual interfaces to communicate CDS recommendations to PCPs, and (d) provides both clinical and cost outcome data useful to clinicians and policymakers. If the EHR- based CDS intervention improves adherence to NHBPEP recommendations, it will provide a much-needed tool to combat the burgeoning problem of rising cardiovascular risk factors in children and adolescents. Further, regardless of outcome, the technology that is developed and tested will provide many useful insights to advance the science of EHR-based CDS. This will, in turn, help translate the massive public and private investments in EHR technology into improved adolescent health outcomes.